Central Locking - drivers door only locks that side

[jimi]

Pity, I'm looking for one to take to bits, see if I can source replacement microswitches.

[LTgoodevil]

Sorry for reviving old thread, but maybe it will be useful for some and keep more MR2 alive . Maybe it will help @jimi replicate the switch as well.
I've recently fixed my door lock central lock by cleaning inside of micro switch.

To do this you will need to disconnect all of the rods connected to lock, disconnect two connectors and maneuver lock out of the door. I've managed to do this by having window in full up position and without disconnecting anything else. Be careful with clips holding rods to the lock, these are snap fit and one connecting to the handle broke for me. Clips are very thin plastics and there would be no way to 3D print them.

Once lock is out central lock switch is attached to the lock by two JIS (Japanese version of Philips head) screws. Mine was very rusty and got destroyed during removal, luckily I found replacement. I've attached photo of the type of screw used, but I don't know the dimensions.

Switch is made of two parts snap fit together. 3 contact are connected to 3 conductor plates on PCB and cover contains joint flexible pins. One pin is always in contact with middle plate and the other pin normally is not touching other two banana shaped plates. When key is turned one way pin touches one of the plates sending signal from centre plate to wire attached to the banana plate. Then key is returned to normal position pin goes back to not touching either plates, turning key other way touches other plate and sends signal over other wire. Banana plates are connected to central locking on/off terminals.

Switch had grease, corrosion and oxidation inside. I wasn't sure if grease was conductive, but clearly it was there to reduce wear of pins sliding over PCB plating and also insulate from water and dust. As I'm fitting remote central lock kit and not too worried about wear, I've cleaned switch with isopropyl alcohol and scraped oxidation from pins and plates using tip of Stanley knife.

Assembled everything back together and Voilà - drivers door key know locks and unlocks both doors

[jimi]

Thanks for posting the info and pics, very useful. I very much doubt I could replicate that type of switch.
Which part of the mechanism actually operates the switch when the key is turned ?

If you have no objection I'll copy the info and pics to a KY2 article ?

[LTgoodevil]

No objection at all.
White elongated part has pin that goes into metal lever mechanism and blue clip connects the rod linking to key on external handle.
Turning key replicates turning motion indicated on microswitch and central locking takes place

[jimi]

Excellent picture, again great info. Thanks
Looks like it might be possible to replace the switch with a commercially available one, would mean some minor mods but appears feasible, I'll need to do a more research and see if I can get my hands on a lock mechanism to experiment on.

[LTgoodevil]

I think PCB part of the switch could be made to order from China and should be quite cheap if ordering 100 or so - I would imagine this is the bit which breaks the most.
Pins could corrod away, but that's just the case of getting some flexible sheet metal and cut new one.
Encloser would be hardest to reproduce, but with CAD and commercial MJF 3D printer would be possible - again would need to order bulk.

If there's a demand I could look into this later this year as currently I'm working on two electrocinical projects that involves 3D printing